Many people aren't aware of the central role the recycling industry plays these days. It pulled in $236 billion in revenues last year and employed more than 1 million people. The industry accounted for about 2 percent of the U.S. gross domestic product in 2007.

The publication identified the following trends benefiting the industry:

•Higher energy costs make recycled materials more economically valuable. Example: energy accounts for 20 percent to 30 percent of the cost to make metals such as aluminum and zinc.